Spans
One page per width, from 40 to 300 ft. Each carries the framing steel and cost at that span, what changes structurally there, what a column line would have saved, and which buildings actually get built that wide.
Every row is priced at the eave height and length that width is normally built at, so the rows are each realistic rather than each comparable — the individual pages state their own case. What to notice is the shape: steel per square foot roughly triples between 40 and 300 ft while the width goes up by seven and a half times, and the modular saving goes from nothing to a third of the package.
| Width | Steel lb/sf | Package $/sf | Installed $/sf | Haunch | Modular saves | What changes at this width |
|---|---|---|---|---|---|---|
| 40 ft | 2.04 – 2.97 lb/sf | $13.45 – $16.33/sf | $20.84 – $31.02/sf | 19–24 in | — | Light frames. Span is rarely the cost driver at this width - eave height and snow load matter more. |
| 60 ft | 3.00 – 4.20 lb/sf | $15.00 – $18.00/sf | $23.25 – $34.20/sf | 29–36 in | — | The practical floor for commercial work. Below this width, small-building suppliers price better. |
| 80 ft | 4.07 – 5.57 lb/sf | $16.63 – $20.79/sf | $25.78 – $39.50/sf | 38–48 in | — | The crossover band. Clear span and modular start to diverge in cost here - price both. |
| 100 ft | 5.26 – 7.32 lb/sf | $18.35 – $22.66/sf | $28.44 – $43.06/sf | 48–60 in | 5% | Haunch depth begins to govern interior clearance. Check usable height, not just the eave. |
| 120 ft | 6.41 – 8.92 lb/sf | $19.43 – $24.82/sf | $30.11 – $47.16/sf | 58–72 in | 9% | Deep haunches and heavier anchor-bolt patterns. Foundation cost stops being a rounding error. |
| 150 ft | 8.26 – 11.56 lb/sf | $21.98 – $28.57/sf | $34.07 – $54.29/sf | 72–90 in | 14% | The practical ceiling for a standard single-span rigid frame. Past this you are buying custom engineering. |
| 200 ft | 11.55 – 16.42 lb/sf | $26.85 – $35.80/sf | $41.62 – $68.02/sf | 96–120 in | 22% | Custom engineering, shipping splices, and heavier erection equipment. Modular usually wins on cost alone. |
| 250 ft | 16.10 – 22.54 lb/sf | $32.44 – $44.02/sf | $50.27 – $83.64/sf | 120–150 in | 28% | Specialist territory. Justified by use, not economics - hangars, arenas, column-free process floors. |
| 300 ft | 21.76 – 31.28 lb/sf | $39.53 – $55.11/sf | $61.28 – $104.71/sf | 144–180 in | 33% | The upper limit most manufacturers offer. Expect a bespoke frame design and a long lead time. |
Planning-stage estimate calibrated to published industry ranges. Not a substitute for a stamped design by a licensed engineer. How every figure here was derived, including what the model cannot do.
40 ft clear span
Buy this building on eave height, snow load, and who is quoting it — not on span. And have a post-frame builder price the same footprint, because at 40 ft they are still in the game.
2.04 – 2.97 lb/sf →60 ft clear span
Clear span, tapered columns, one crane, catalog engineering, no splices. This is the easiest building in the table to buy, and the width where competitive quoting really begins.
3.00 – 4.20 lb/sf →80 ft clear span
Price both. At exactly this width clear span and modular should come back within a percent or two of each other, which means the layout — not the structure — should decide it.
4.07 – 5.57 lb/sf →100 ft clear span
Specify the clear height you need under the haunch, not the eave height you want. Every foot you find out about late is a foot of wall panel you pay for and cannot use.
5.26 – 7.32 lb/sf · modular saves 5% →120 ft clear span
Get the foundation priced with the building, not after it. At this width a thrust detail the steel quote never mentions can cost more than the gap between two frame quotes.
6.41 – 8.92 lb/sf · modular saves 9% →150 ft clear span
This is the widest building you can expect fast, competitive, comparable quotes on. If your width is near 150 and flexible, coming down to it rather than going up is worth real money.
8.26 – 11.56 lb/sf · modular saves 14% →200 ft clear span
You should be able to name the thing that makes the column impossible — a hangar door, a crane runway, a process floor. If you cannot, modular saves you 22% and you should take it.
11.55 – 16.42 lb/sf · modular saves 22% →250 ft clear span
Get more than one manufacturer, and get the deflection criteria into the specification before anyone prices it. Two bids to two different deflection limits are not comparable.
16.10 – 22.54 lb/sf · modular saves 28% →300 ft clear span
If you need more than 300 ft of width you need multi-gable or modular framing. There is no single-span answer above here, and asking for one mostly buys you silence from bidders.
21.76 – 31.28 lb/sf · modular saves 33% →Package cost per square foot at each width's own typical eave and length. The card headline is a price, not a recommendation — the page behind it says what the width is good for.
Nine pages is more granularity than most projects need. If you are scoping rather than pricing, three numbers do most of the work:
Below this width post-frame, bar joist on masonry and light tube-frame suppliers all still compete, and the dealers who specialise in commercial rigid frames are not the ones you want quoting. Above it the rigid frame is the obvious system and the market is deep. What changes at 60 ft.
Below it, an interior column saves nothing and clear span is free. Above it, the two configurations diverge and keep diverging, so from here you should be able to say what the clear floor is for. The crossover, in detail.
This is the practical ceiling for a standard single-span rigid frame. Below it you configure something a manufacturer already builds and get comparable quotes in days. Above it you commission a frame: project-specific engineering, fewer bidders, longer lead times, and bids that are harder to compare. The last catalog frame.
The span table has ten rows and this section has nine pages. 50 ft was cut, because everything true of it was already true of 40 ft: the same tier below commercial work, the same zero saving from a column line, the same straight columns, the same one-piece rafters on an ordinary flatbed, the same catalog engineering, the same applications. Only the interpolated dollars differed, and a page whose only distinguishing feature is its own price is a page that should not exist. 50 ft is still a row in the span table and the calculators still price it exactly.
If your building is a width without a page — and most are — the clear span calculator interpolates between the table rows and prices any width from 40 to 300 ft, with your own eave height, bay spacing and design loads rather than a representative case.